Many parts managers still run their DMS with 2 or 3 sources because older systems pushed everything into broad categories. Chuck Hartle explained that modern DMS platforms can support far more segmentation. When managers increase source count, they stop forcing fast movers, maintenance items, accessories, and slow movers into the same rule set. That reduces manual pricing fixes and removes the need for tracking exceptions outside the system.
A higher number of sources gives managers control over pricing, order rules, returns, and day supply. Instead of bending 1 rule to cover every item, each group can operate on standards that match movement.
Chuck Hartle stated that 12 to 20 sources are manageable without outside support because source-by-movement logic simplifies decisions. When categories are grouped by behavior, the manager does not chase exceptions. With support tools, going past 20 is practical because the data is organized at the source level. This prevents fast movers from carrying excess stock weight for slower groups.
It protects spending as well. Instead of adjusting everything globally, the manager can apply changes to a defined category.
Correct stocking levels change based on how often a part sells. High demand parts benefit from leaner stocking levels to prevent accumulation. Low demand parts need measured cushion so the department avoids an empty bin. A blended source removes that flexibility and forces a compromise that fits neither group.
Chuck Hartle said that average obsolescence across the industry now sits near 20%. Zero remains the target but current supply conditions make that difficult. Managers gain leverage by monitoring aging at 7 to 12 months, controlling special orders, and acting on returns before parts lock in permanently. When aging is viewed by source, exposure becomes easier to address because each category is isolated.
Separate sources allow managers to isolate parts tied to RIM, incentives, captive maintenance, or marketing programs. Without separation, incentive orders inflate stock levels and introduce long-term exposure. Tracking these parts independently lets a manager benefit from short-term programs without contaminating regular stocking patterns.
Chuck Hartle also warned against writing obsolete parts down to $0.01. The habit hides the financial impact and causes commission payouts against false gross. Writing down at cost gives the store realistic numbers and prevents compensation based on imaginary margin.
Increasing DMS sources creates structure. Structure supports pricing control, day supply decisions, aging management, and program oversight. When a parts department separates inventory by behavior instead of forcing global rules, it limits obsolescence and improves turn. The result is control instead of reaction.
“Inventory shouldn’t be a guessing game.” — Chuck Hartle